1. Field of the Invention
The present disclosure generally relates to pharmaceutical compositions useful for the treatment of diseases and disorders. More particularly, the disclosure relates to pharmaceutical compositions comprising glyceryl tribenzoate and/or glyceryl dibenzoate for the treatment of urea cycle disorders and neurodegenerative disorders.
2. Description of the Related Art
Cinnamon, the brown bark of cinnamon tree, is a commonly used spice and flavoring material for desert, candies, chocolate etc. It has a long history of being used as medicine as well. Medieval physicians used cinnamon in medicines to treat a variety of disorders, including arthritis, coughing, hoarseness, sore throats, etc. In addition to containing manganese, dietary fiber, iron, and calcium, cinnamon contains three major compounds—cinnamaldehyde, cinnamyl acetate and cinnamyl alcohol. After intake, these three active compounds are converted into cinnamic acid by oxidation and hydrolysis, respectively. Then, cinnamic acid is β-oxidized to benzoate in the liver. This benzoate exists as sodium salt (sodium benzoate) or benzoyl-CoA.
Sodium benzoate is a widely-used food preservative due to its anti-microbial properties. It also has medical importance as a component of Ucephan™, a Food and Drug Administration (FDA)-approved drug used in the treatment for hepatic metabolic defects associated with hyperammonemia, such as urea cycle disorder. The present inventor explored a novel use of sodium benzoate in treating the disease process of relapsing-remitting EAE in female SJL/J mice (see Brahmachari and Pahan, “Sodium benzoate, a food additive and a metabolite of cinnamon, modifies T cells at multiple steps and inhibits adoptive transfer of experimental allergic encephalomyelitis,” J. Immunol., 2007, Jul. 1; 179(1):275-83, the entire contents of which are expressly incorporated into the present application by reference).
The present inventor also discovered that sodium benzoate suppresses the disease process of multiple sclerosis (MS) in mice. The inventor has also discovered that sodium benzoate up-regulates a protein called DJ-1, which is a beneficial, neuroprotective protein having implications in neurodegenerative disorders, such as Parkinson's disease (PD) and Alzheimer's disease (AD) (see Khasnavis and Pahan, “Sodium Benzoate, a Metabolite of Cinnamon and a Food Additive, Upregulates Neuroprotective Parkinson Disease Protein DJ-1 in Astrocytes and Neurons,” Journal of Neuroimmune Pharmacology, June 2012, Volume 7, Issue 2, pp 424-435, the entire contents of which are expressly incorporated into the present application by reference).
Further, it has been found that the level of neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), decreases in the brain of patients with different neurodegenerative disorders, such as AD and PD. Recently, the present inventor delineated that sodium benzoate increases the production of BDNF and NT-3 in brain cells, indicating that it could be beneficial for neurodegenerative disorders (see Jana et al., “Up-regulation of neurotrophic factors by cinnamon and its metabolite sodium benzoate: therapeutic implications for neurodegenerative disorders,” J. Neuroimmune Pharmacol., 2013 June; 8(3):739-55, the entire contents of which are expressly incorporated into the present application by reference).
However, sodium benzoate is quickly metabolized and excreted from the body. Therefore, sodium benzoate is generally administered three to four times per day, at least in connection with urea cycle disorders, in order to ensure continual removal of toxic ammonia from the bloodstream.